He succeeds ex-Sligo Rovers boss Paul Cook
Portsmouth have appointed Kenny Jackett as manager in preparation for life back in League One.
They were promoted from the fourth tier as champions last month but former Sligo Rovers boss Paul Cook has since left to take over as manager at Wigan Athletic.
Jackett has been out of work following a brief spell as Rotherham United boss.
He resigned in November just five games into his tenure with the now relegated Championship club.
Reacting to his move to Portsmouth, Jackett said: "This is a fantastic opportunity for me and I’m looking forward to getting started. It’s an exciting challenge.
"This club has a passionate fan-base and they can be a 12th man for us. Hopefully we can build on the momentum of last season and continue to progress.
"I can promise that I’ll work as hard as I possibly can to make sure that we can bring success to Portsmouth."